Fused coupler forming with a single-mode fiber (SMF) and a photonic crystal fiber (PCF) is one of the solutions for optical coupling from a light source to a PCF. In this paper, we presented coupling characteristics of a fused fiber coupler formed with an ordinary SMF and a PCF having air hole collapsed taper. A prototype of SMF-PCF coupler with air hole collapsed taper was fabricated using CO<sub>2</sub> laser irradiation. The coupling efficiency from SMF to PCF was &#x2212;6.2&#x2009;dB at 1554&#x2009;nm wavelength in the fabricated coupler. The structure of the SMF-PCF coupler to obtain high coupling efficiency was theoretically clarified by beam propagation analysis using an equivalent model of the coupler with simplification. It was clarified that appropriately choosing the prestretched or etched SMF diameter and the length of air hole collapsed region was effective to obtain high coupling efficiency that was a result of high extinction ratio at cross port and low excess loss. We also demonstrated that the diameter of prestretched SMF to obtain high coupling efficiency was insensitive to the air hole diameter ratio to pitch of the PCF in the air hole collapsed SMF-PCF coupler.

Hirohisa Yokota

Hirotomo Yashima

Yoh Imai

Yutaka Sasaki

Coupling Characteristics of Fused Optical Fiber Coupler Formed with Single-Mode Fiber and Photonic Crystal Fiber Having Air Hole Collapsed Taper

A simple iterative optimization method is developed to improve the exiting light uniformity of the edge-lit backlight module. The method uses the relative deviation of the average luminous flux of the entire light guide plate (LGP) and the luminous flux of each region as constraint criterion and the ratio of the luminous flux of each region to the average luminous flux of the LGP as adjustment coefficient to adjust the density of the microstructures in each region. This process loops until the relative deviations of all regions meet a prespecified threshold value. A LGP based on microprism structure is presented to validate the method. The initial values, which represent the size of the microstructures manufactured on the bottom surfaces of the LGP, <svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-3.29107pt" id="M1" height="12.5794pt" version="1.1" viewBox="-0.0498162 -9.28833 12.2229 12.5794" width="12.2229pt"><g transform="matrix(.013,0,0,-0.013,0,0)"><path id="g113-101" d="M530 686C535 705 530 712 521 712C504 712 448 684 359 674L358 648H393C437 648 439 646 429 593L400 435C372 447 345 448 332 448C286 448 194 414 144 373C68 311 23 203 23 111C23 26 57 -12 91 -12C120 -12 147 3 188 29C227 54 290 102 341 170H343L322 71C308 6 320 -12 341 -12C373 -12 442 27 501 96L485 120C455 91 422 67 408 67C401 67 401 76 404 91C440 294 479 473 530 686ZM387 375L355 241C326 187 200 53 142 53C126 53 109 73 109 130C109 217 154 337 218 381C240 396 265 404 297 404S372 390 387 375Z"/></g><g transform="matrix(.0091,0,0,-0.0091,7.15,3.132)"><path id="g50-49" d="M245 635C92 635 37 457 37 312C37 149 91 -12 244 -12C395 -12 449 166 449 312C449 469 395 635 245 635ZM243 598C332 598 358 454 358 312C358 173 334 26 245 26C158 26 128 174 128 313S152 598 243 598Z"/></g></svg>-dependent luminous fluxes, microstructure size distributions, iterations of the LGP, and the relative deviation of each region are discussed. The simulation results show that it is a very practical method for the uniformity improvement of the backlight when an appropriate initial value is selected and the final uniformity is better than 90% after optimization.

Jin-Ren Yan

De-Cong Li

Zhi-Kun Wang

Wen-Ping Rao

An Iterative Method for the Uniformity Improvement of Edge-Lit Backlight

A novel high birefringence and nearly zero dispersion-flattened photonic crystal fiber (PCF) with elliptical defected core (E-DC) and equilateral pentagonal architecture is designed. By applying the full-vector finite element method (FEM), the characteristics of electric field distribution, birefringence, and chromatic dispersion of the proposed E-DC PCF are numerically investigated in detail. The simulation results reveal that the proposed PCF can realize high birefringence, ranging from 1<svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-0.2063999pt" id="M1" height="11.7978pt" version="1.1" viewBox="-0.0498162 -11.5914 16.8904 11.7978" width="16.8904pt"><g transform="matrix(.013,0,0,-0.013,0,0)"><path id="g113-49" d="M241 635C89 635 35 457 35 312C35 153 89 -12 240 -12C390 -12 443 166 443 312C443 466 390 635 241 635ZM238 602C329 602 354 454 354 312C354 172 330 22 240 22C152 22 124 173 124 313S148 602 238 602Z"/></g><g transform="matrix(.0091,0,0,-0.0091,6.24,-5.741)"><path id="g54-33" d="M556 236V289H56V236H556Z"/></g><g transform="matrix(.0091,0,0,-0.0091,11.8,-5.741)"><path id="g50-52" d="M290 377C321 398 342 415 358 430C378 450 389 473 389 502C389 578 329 635 238 635H237C184 635 137 610 109 578L64 515L88 493C112 529 154 573 208 573S303 542 303 482C303 409 233 370 141 341L149 308C165 313 190 319 215 319C272 319 341 283 341 193C342 98 292 43 222 43C163 43 122 72 96 94C88 101 79 100 70 94C61 87 47 73 46 60C44 47 48 37 62 23C76 10 118 -12 165 -12C238 -12 430 62 430 223C430 297 379 359 290 375V377Z"/></g></svg> to 1<svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-0.2063999pt" id="M2" height="11.7978pt" version="1.1" viewBox="-0.0498162 -11.5914 16.8904 11.7978" width="16.8904pt"><g transform="matrix(.013,0,0,-0.013,0,0)"><use xlink:href="#g113-49"/></g><g transform="matrix(.0091,0,0,-0.0091,6.24,-5.741)"><use xlink:href="#g54-33"/></g><g transform="matrix(.0091,0,0,-0.0091,11.8,-5.741)"><path id="g50-51" d="M414 144C384 79 371 75 317 75H135L276 221C367 316 408 376 408 465C408 570 327 635 237 635C179 635 131 609 100 575L42 494L67 471C94 510 138 565 205 565C277 565 321 517 321 435C321 348 258 270 195 195C146 137 88 81 33 26V0H411C423 44 433 88 446 135L414 144Z"/></g></svg> orders of magnitude, owing to the embedded elliptical air hole in the core center. However, the existence of the elliptical air hole gives rise to an extraordinary electric field distribution, where a V-shaped notch appears and the size of the V-shaped notch varies at different operating wavelengths. Also, the mode field diameter is estimated to be about 2 <i>μ</i>m, which implies the small effective mode area and highly nonlinear coefficient. Furthermore, the investigation of the chromatic dispersion characteristic shows that the introduction of the elliptical air hole is helpful to control the chromatic dispersion to be negative or nearly zero flattened over a wide wavelength bandwidth.

Fei Yu

Zhenpeng Wang

Wenhao Yang

Chongyang Lv

Characteristics of Highly Birefringent Photonic Crystal Fiber with Defected Core and Equilateral Pentagon Architecture

The light polarization effects on the optical reflective and dielectric spectra of GaSe thin films are studied in the incident light wavelength range of 200–1100 nm. In this range of measurement, the angle of incidence (<svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-3.29107pt" id="M1" height="12.5794pt" version="1.1" viewBox="-0.0498162 -9.28833 9.32736 12.5794" width="9.32736pt"><g transform="matrix(.013,0,0,-0.013,0,0)"><path id="g113-230" d="M475 507C475 612 440 712 326 712C139 712 23 420 23 215C23 96 58 -12 180 -12C369 -12 475 293 475 507ZM391 522C391 486 387 448 379 394H126C155 538 222 677 310 677C386 677 391 571 391 522ZM373 346C344 193 283 22 189 22C126 22 106 114 106 196C106 243 111 293 118 346H373Z"/></g><g transform="matrix(.0091,0,0,-0.0091,6.149,3.132)"><path id="g50-106" d="M250 606C250 634 233 656 203 656C168 656 146 618 146 593C146 564 169 545 192 545C227 545 250 573 250 606ZM227 95L212 119C187 98 152 71 135 71C129 71 128 78 134 102L207 373C219 418 217 451 194 451C165 451 92 411 30 351L44 326C77 353 106 371 114 371C124 371 121 357 117 341L55 97C32 5 46 -12 70 -12C108 -12 191 51 227 95Z"/></g></svg>) of light was varied between 30° and 80°. In addition, at <svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-3.29107pt" id="M2" height="12.5794pt" version="1.1" viewBox="-0.0498162 -9.28833 9.32736 12.5794" width="9.32736pt"><g transform="matrix(.013,0,0,-0.013,0,0)"><use xlink:href="#g113-230"/></g><g transform="matrix(.0091,0,0,-0.0091,6.149,3.132)"><use xlink:href="#g50-106"/></g></svg> of 30° the light polarizing angle (<svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-0.2063999pt" id="M3" height="9.49473pt" version="1.1" viewBox="-0.0498162 -9.28833 6.84582 9.49473" width="6.84582pt"><g transform="matrix(.013,0,0,-0.013,0,0)"><path id="g113-226" d="M494 514C482 587 419 712 303 712C238 712 174 667 174 603C174 561 205 514 249 449C219 438 187 422 162 407C93 366 23 283 23 177C23 69 87 -12 190 -12C244 -12 288 5 328 33C406 87 444 170 444 249C444 329 404 391 331 475C265 550 222 605 222 627C222 647 238 657 267 657C355 657 421 585 484 499L494 514ZM359 234C359 143 319 30 219 30C172 30 114 75 114 178C114 275 163 343 195 378C212 397 241 415 269 425C305 382 359 313 359 234Z"/></g></svg>) was altered in the range of 0–90°. Regardless of the value of <svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-0.2063999pt" id="M4" height="9.49473pt" version="1.1" viewBox="-0.0498162 -9.28833 7.30254 9.49473" width="7.30254pt"><g transform="matrix(.013,0,0,-0.013,0,0)"><path id="g113-233" d="M529 97L508 118C475 75 449 58 438 58C428 58 421 66 415 104C393 234 374 403 364 496C345 670 307 712 254 712C220 712 174 691 153 669L161 645C176 653 194 658 206 658C237 658 261 640 278 562C287 522 290 483 293 434C223 269 110 105 23 9L32 -12C59 -6 85 0 108 7C152 64 251 252 300 366C307 297 315 221 337 82C346 24 363 -12 393 -12C425 -12 475 13 529 97Z"/></g></svg>, for all <svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-3.291101pt" id="M5" height="14.0878pt" version="1.1" viewBox="-0.0498162 -10.7967 40.7922 14.0878" width="40.7922pt"><g transform="matrix(.013,0,0,-0.013,0,0)"><use xlink:href="#g113-230"/></g><g transform="matrix(.0091,0,0,-0.0091,6.149,3.132)"><use xlink:href="#g50-106"/></g><g transform="matrix(.013,0,0,-0.013,12.836,0)"><path id="g117-108" d="M512 230V280H510C349 280 196 365 126 514L75 490C128 377 228 295 347 256V254C228 215 128 134 75 21L126 -3C196 146 349 230 510 230H512Z"/></g><g transform="matrix(.013,0,0,-0.013,24.099,0)"><path id="g113-55" d="M137 343C167 482 260 545 321 574C357 591 397 603 429 609L423 641C382 634 335 622 295 608C189 570 37 457 37 238C37 84 125 -12 242 -12C362 -12 447 89 447 209C447 311 374 393 267 393C247 393 226 386 204 376L137 343ZM227 337C318 337 361 256 361 173C361 105 336 22 258 22C176 22 126 120 126 240C126 266 127 291 132 310C155 323 189 337 227 337Z"/></g><g transform="matrix(.013,0,0,-0.013,30.34,0)"><path id="g113-54" d="M153 550H386L412 615L406 623H120L82 318C104 327 142 338 184 338C294 338 347 275 347 187C347 112 305 39 221 39C160 39 119 71 97 89C88 97 80 96 71 90C59 80 50 67 49 57C48 45 52 36 66 23C80 9 123 -12 169 -12C221 -11 288 15 342 59C403 109 431 165 431 225C431 308 366 395 238 395C212 395 165 379 127 364L153 550Z"/></g><g transform="matrix(.0091,0,0,-0.0091,36.58,-5.741)"><path id="g54-73" d="M339 262C339 340 273 403 193 403S48 340 48 262S113 121 193 121S339 184 339 262ZM283 262C283 210 242 168 193 168S104 210 104 262S144 356 193 356S283 314 283 262Z"/></g></svg>, the total reflectance sharply decreased with increasing <svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-3.29107pt" id="M6" height="12.5794pt" version="1.1" viewBox="-0.0498162 -9.28833 9.32736 12.5794" width="9.32736pt"><g transform="matrix(.013,0,0,-0.013,0,0)"><use xlink:href="#g113-230"/></g><g transform="matrix(.0091,0,0,-0.0091,6.149,3.132)"><use xlink:href="#g50-106"/></g></svg>. In addition, when <svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-3.29107pt" id="M7" height="12.5794pt" version="1.1" viewBox="-0.0498162 -9.28833 9.32736 12.5794" width="9.32736pt"><g transform="matrix(.013,0,0,-0.013,0,0)"><use xlink:href="#g113-230"/></g><g transform="matrix(.0091,0,0,-0.0091,6.149,3.132)"><use xlink:href="#g50-106"/></g></svg> is fixed at 30° and <svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-0.2063999pt" id="M8" height="9.49473pt" version="1.1" viewBox="-0.0498162 -9.28833 6.84582 9.49473" width="6.84582pt"><g transform="matrix(.013,0,0,-0.013,0,0)"><use xlink:href="#g113-226"/></g></svg> was varied, the amplitudes ratio of the polarized waves exhibits a resonance-antiresonance phenomenon at a wavelength that coincides with the film’s thickness (800 nm). This behavior was assigned to the coupled interference between incident and reflected waves and to the strong absorption effects. Two main resonance peaks are observed as response to <svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-0.2063904pt" id="M9" height="6.1673pt" version="1.1" viewBox="-0.0498162 -5.96091 4.9929 6.1673" width="4.9929pt"><g transform="matrix(.013,0,0,-0.013,0,0)"><path id="g113-116" d="M352 391C352 416 319 448 267 448C236 448 173 423 147 400C107 364 96 332 96 304C96 248 143 210 193 181C241 153 258 124 258 100C258 72 232 38 184 38C151 38 107 66 81 108C77 114 64 116 55 111C34 99 23 84 23 65C23 29 81 -12 134 -12C220 -12 325 61 325 141C325 184 297 215 234 256C194 282 161 309 161 346C161 380 188 401 217 401C255 401 279 380 301 353C308 344 313 341 325 347C341 355 352 371 352 391Z"/></g></svg>-polarized and normal incident beam: one is at ~540 (556 nm) and the other at ~420 THz (714 nm). The dielectric constant of the GaSe films exhibits anisotropic characteristics that nominate it for use as multipurpose optoelectronic devices.

Hazem K. Khanfar

Atef A. Qasrawi

Polarization Sensitive Reflection and Dielectric Spectra in GaSe Thin Films

The feasibility of polarization-maintaining photonic crystal fibre (PM-PCF) strategy for acoustooptic modulation using all-fibre Sagnac interferometer is demonstrated. The principal constraint to apply the strategy is defined by a linear laser acoustooptic modulator (AOM) for 1550 nm. The intensity of incident acoustic waves over the PM-PCF loop segment affected the signal interference transmission; here, modulation by birefringence variation around <svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-3.2911pt" id="M1" height="14.8825pt" version="1.1" viewBox="-0.0498162 -11.5914 83.502 14.8825" width="83.502pt"><g transform="matrix(.013,0,0,-0.013,0,0)"><path id="g113-56" d="M447 623H65C61 580 56 530 47 475H76C100 541 106 550 172 550H388C308 376 196 170 91 -1L98 -12L172 -2C268 204 360 408 455 611L447 623Z"/></g><g transform="matrix(.013,0,0,-0.013,6.242,0)"><path id="g113-47" d="M113 -12C146 -12 170 11 170 46C170 78 146 103 114 103S58 78 58 46C58 11 82 -12 113 -12Z"/></g><g transform="matrix(.013,0,0,-0.013,9.206,0)"><path id="g113-55" d="M137 343C167 482 260 545 321 574C357 591 397 603 429 609L423 641C382 634 335 622 295 608C189 570 37 457 37 238C37 84 125 -12 242 -12C362 -12 447 89 447 209C447 311 374 393 267 393C247 393 226 386 204 376L137 343ZM227 337C318 337 361 256 361 173C361 105 336 22 258 22C176 22 126 120 126 240C126 266 127 291 132 310C155 323 189 337 227 337Z"/></g><g transform="matrix(.013,0,0,-0.013,18.352,0)"><path id="g117-42" d="M528 54L331 254L528 455L492 493L294 291L96 493L60 455L257 254L60 54L96 16L294 217L492 16L528 54Z"/></g><g transform="matrix(.013,0,0,-0.013,28.888,0)"><path id="g113-50" d="M384 0V27C293 34 287 42 287 114V635C232 613 172 594 109 583V559L157 557C201 555 205 550 205 499V114C205 42 199 34 109 27V0H384Z"/></g><g transform="matrix(.013,0,0,-0.013,35.128,0)"><path id="g113-49" d="M241 635C89 635 35 457 35 312C35 153 89 -12 240 -12C390 -12 443 166 443 312C443 466 390 635 241 635ZM238 602C329 602 354 454 354 312C354 172 330 22 240 22C152 22 124 173 124 313S148 602 238 602Z"/></g><g transform="matrix(.0091,0,0,-0.0091,41.415,-5.741)"><path id="g54-33" d="M556 236V289H56V236H556Z"/></g><g transform="matrix(.0091,0,0,-0.0091,46.975,-5.741)"><path id="g50-53" d="M462 177V227H365V632H320C217 496 116 350 21 208V177H284V109C284 43 280 38 190 31V0H451V31C369 38 365 43 365 108V177H462ZM284 227H88C155 336 218 430 282 519H284V227Z"/></g><g transform="matrix(.013,0,0,-0.013,54.848,0)"><path id="g117-37" d="M535 290V340H323V533H265V340H52V290H265V84H323V290H535ZM535 -22V28H52V-22H535Z"/></g><g transform="matrix(.013,0,0,-0.013,65.384,0)"><path id="g113-133" d="M600 0V24L339 665L311 657L43 24V0H600ZM497 50H107L303 539L497 50Z"/></g><g transform="matrix(.013,0,0,-0.013,73.712,0)"><path id="g113-111" d="M495 86L479 114C446 82 419 66 409 66C401 66 401 72 406 97C420 166 436 231 453 297C489 435 454 448 428 448C406 448 384 439 354 422C305 394 222 327 161 247H159L183 345C200 415 194 448 173 448C143 448 82 410 23 351L38 325C64 349 95 371 105 371C111 371 116 365 109 336L25 -4L31 -12C50 -4 77 3 107 9C119 69 132 122 145 168C197 254 321 381 370 381C387 381 393 374 378 305L329 95C309 17 320 -12 345 -12C372 -12 430 19 495 86Z"/></g><g transform="matrix(.0091,0,0,-0.0091,80.172,3.132)"><path id="g50-106" d="M250 606C250 634 233 656 203 656C168 656 146 618 146 593C146 564 169 545 192 545C227 545 250 573 250 606ZM227 95L212 119C187 98 152 71 135 71C129 71 128 78 134 102L207 373C219 418 217 451 194 451C165 451 92 411 30 351L44 326C77 353 106 371 114 371C124 371 121 357 117 341L55 97C32 5 46 -12 70 -12C108 -12 191 51 227 95Z"/></g></svg> was observed. It is discovered that, through mathematical analysis, two operation points in the spectrum, <svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-3.29567pt" id="M2" height="12.584pt" version="1.1" viewBox="-0.0498162 -9.28833 31.5324 12.584" width="31.5324pt"><g transform="matrix(.013,0,0,-0.013,0,0)"><path id="g113-85" d="M620 675H597C578 656 570 650 541 650H144C112 650 104 653 94 675H72C59 618 42 552 23 493L53 491C71 534 88 564 105 585C124 608 144 615 238 615H290L197 121C182 40 174 34 88 28L82 0H361L367 28C275 34 266 38 281 121L374 615H441C522 615 543 608 553 583C562 560 566 531 565 493L597 494C603 551 612 629 620 675Z"/></g><g transform="matrix(.0091,0,0,-0.0091,7.176,3.132)"><path id="g58-81" d="M416 501L399 642C356 655 314 665 271 665C140 665 63 582 63 486C63 372 163 325 229 290C304 250 359 217 359 142C359 70 316 25 240 25C138 25 94 125 78 186L44 178C52 123 64 45 72 21C81 16 96 8 121 0S179 -15 220 -15C353 -15 445 68 445 176C445 289 350 335 270 375C191 414 143 449 143 520C143 572 177 627 253 627C340 627 366 556 382 495L416 501Z"/></g><g transform="matrix(.0091,0,0,-0.0091,11.48,3.132)"><path id="g58-71" d="M308 0V33C225 38 217 44 217 128V521C217 605 225 612 308 617V650H39V617C122 612 130 605 130 521V128C130 44 122 38 39 33V0H308Z"/></g><g transform="matrix(.013,0,0,-0.013,15.173,0)"><path id="g113-41" d="M300 -147C201 -63 143 98 143 270S200 602 300 686L282 710C136 610 70 450 70 271V270C70 89 136 -72 282 -170L300 -147Z"/></g><g transform="matrix(.013,0,0,-0.013,19.671,0)"><path id="g113-233" d="M529 97L508 118C475 75 449 58 438 58C428 58 421 66 415 104C393 234 374 403 364 496C345 670 307 712 254 712C220 712 174 691 153 669L161 645C176 653 194 658 206 658C237 658 261 640 278 562C287 522 290 483 293 434C223 269 110 105 23 9L32 -12C59 -6 85 0 108 7C152 64 251 252 300 366C307 297 315 221 337 82C346 24 363 -12 393 -12C425 -12 475 13 529 97Z"/></g><g transform="matrix(.013,0,0,-0.013,26.845,0)"><path id="g113-42" d="M275 270C275 450 212 609 64 710L45 686C145 604 203 442 203 270S147 -63 45 -147L64 -170C213 -68 275 89 275 270Z"/></g></svg>, operate in a linear region, and expressions for spectral gain and sensibility are also discovered. AOM has a bandwidth from 0.1 Hz to 20 kHz, and its dynamic range is from 0.0 to 43.5 dB.

G. Trinidad Garc&#xed;a

E. Molina Flores

B. A. Ram&#xed;rez Sol&#xed;s

H. Azucena Coyotecatl

Study of a Linear Acoustooptic Laser Modulator Based on All-Fibre Sagnac Interferometer

The formation dynamics of the optical noise in a silica single mode fiber (SMF) as function of the pump power variation in the counter pumped fiber Raman amplifier (FRA) is experimentally studied. The ratio between the power of amplified spontaneous emission and the power of incoherent optical noise is quantitatively determined by detailed analysis of experimental data in the pump powers range of 100&#x2013;300&#x2009;mW within the full band of Stokes frequencies, including FRA working wavelengths over the C + L transparency windows. It is found out the maximum of Raman gain coefficient for optical noise does not exceed &#x7e;60&#x25; of corresponding peak at the gain profile maximum of coherent signal. It is shown that the real FRA noise figure may be considerably less than 3&#x2009;dB over a wide wavelength range (100&#x2009;nm) at a pump power of several hundreds of mW.

Georgii S. Felinskyi

Mykhailo Y. Dyriv

Noise Gain Features of Fiber Raman Amplifier

The grooming node has the capability of grooming multicast traffic with the small granularity into established light at high cost of complexity and node architecture. In the paper, a grooming nodes optimal allocation (GNOA) method is proposed to optimize the allocation of the grooming nodes constraint by the blocking probability for multicast traffic in sparse WDM networks. In the proposed GNOA method, the location of each grooming node is determined by the SCLD strategy. The improved smallest cost largest degree (SCLD) strategy is designed to select the nongrooming nodes in the proposed GNOA method. The simulation results show that the proposed GNOA method can reduce the required number of grooming nodes and decrease the cost of constructing a network to guarantee a certain request blocking probability when the wavelengths per fiber and transmitter/receiver ports per node are sufficient for the optical multicast in WDM networks.

Chengying Wei

Qinren Shen

Huanlin Liu

Yong Chen

A Grooming Nodes Optimal Allocation Method for Multicast in WDM Networks

Internal photoemission (IP) correlates with processes in which carriers are photoexcited and transferred from one material to another. This characteristic allows characterizing the properties of the heterostructure, for example, the band parameters of a material and the interface between two materials. IP also involves the generation and collection of photocarriers, which leads to applications in the photodetectors. This review discusses the generic IP processes based on heterojunction structures, characterizing <svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-3.42943pt" id="M1" height="10.2124pt" version="1.1" viewBox="-0.0498162 -6.78297 7.83752 10.2124" width="7.83752pt"><g transform="matrix(.013,0,0,-0.013,0,0)"><path id="g113-113" d="M570 304C570 398 525 448 414 448C385 448 343 445 312 434L329 511L321 518C297 504 262 482 244 460L233 411C195 397 159 381 128 358L135 332C160 347 189 360 224 373L111 -147C97 -210 84 -218 17 -231L13 -257L254 -247L259 -218L233 -216C183 -212 177 -202 189 -142L218 -1C238 -10 266 -12 283 -12C351 3 429 48 483 105C543 168 570 242 570 304ZM482 289C482 161 380 33 304 33C278 33 248 51 233 69L303 396C326 400 352 403 369 403C428 403 482 380 482 289Z"/></g></svg>-type band structure and the band offset at the heterointerface, and infrared photodetection including a novel concept of photoresponse extension based on an energy transfer mechanism between hot and cold carriers. 

Y. F. Lao

A. G. U. Perera

Physics of Internal Photoemission and Its Infrared Applications in the Low-Energy Limit

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<p>Advances in OptoElectronics publishes papers on the theory, design, fabrication, and applications of devices and components that convert light into an electrical current or, conversely, an electric current into light.</p>


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Advances in OptoElectronics - Table of contents 2016

title

Advances in OptoElectronics ceased publication in 2019 and is no longer accepting submissions.

description

Advances in OptoElectronics publishes papers on the theory, design, fabrication, and applications of devices and components that convert light into an electrical current or, conversely, an electric current into light.

Advances in OptoElectronics